Well she used a styrofoam box filled with more bits of styrofoam and a heat pack in one corner, and the betta in a diagonal corner, double bagged and wrapped in newspaper. The water level was 1/3 to 1/2 of the bag. I've never had a problem with her, either...but USPS practically stuffed him into my mail box. It was probably their poor handling with the poor little guy.

Actually, not really...the bag might have wiggled around a little, but it didn't have much space to go. There was only three or four rather thin, small strips of styrofoam...maybe 1/4 inch thick, two-three pieces about 2'' by 2.5'' and one bigger one about 3'' by 4''